Nebreda Manjón, JeniferPeláez Sagredo, José RamónRios, G.2023-06-202023-06-202011-04-111550-799810.1103/PhysRevD.83.094011https://hdl.handle.net/20.500.14352/44831©2011 American Physical Society. We thank J. Dudek for lattice results and detailed explanations. Our work was partially supported by the Spanish Ministerio de Educación y Ciencia research Contract Nos.: FPA2007-29115-E, FPA2008-00592 and FIS2006-03438, and U. Complutense/Banco Santander Grant Nos. PR34/07-15875-BSCH and UCM-BSCH GR58/08 910309. We acknowledge the support of the European Community-Research Infrastructure Integrating Activity Study of Strongly Interacting Matter (acronym HadronPhysics2, Grant Agreement No. 227431) under the Seventh Framework Programme of the European Union.We calculate the pion-pion elastic scattering phase shifts for pion masses from the chiral limit to values of interest for lattice studies. At low energies, we use the standard Chiral Perturbation Theory expressions to one and two loops. In addition, we study the phase shifts' mass dependence in the resonance region by means of dispersion theory in the form of unitarized Chiral Perturbation Theory and the inverse amplitude method. We pay particular attention to the case when resonances are close to threshold, illustrating the different behavior between scalar and vector resonances. We also provide the estimation of uncertainties, which are dominated by those of the O[p^(6)] chiral parameters.engjournal articlehttp://dx.doi.org/10.1103/PhysRevD.83.094011http://journals.aps.org/open access51-73Gev-cPolarized targetHigh statisticsLight scalarsSpin-1 fieldsLow-energyMassLagrangiansDecaysπ&πFísica-Modelos matemáticosFísica matemática